Survival rates for colon cancer are determined by biopsies of lymph nodes
If you are diagnosed with colon cancer, the tumor is surgically removed and the lymph nodes surrounding the tumor will be sent to a pathologist for microscopic inspection. Although there are hundreds of lymph nodes near the colon wall, the pathologist will typically check 30 to 40 of the lymph nodes for signs of the cancer cells and with colo-rectal cancer, the type of cancer cells are called adenocarcinoma. The pathology results are available in 2-3 days after the surgery and results of the pathological inspection of the lymph nodes will have all of the answers as to the patient's five year survival rate and prognosis.
If the pathological inspection of the lymph nodes shows no sign of cancer cells, then the colon cancer is most likely confined to the wall of the colon. This is a good sign for the patient. If the tumor has not spread outside the wall of the colon, the patient's five year survival rate is very good, i.e., better than 50%. Five year survival rate is the statistical likelihood that the patient will be alive five years after the cancer diagnosis.
If the pathological inspection of the lymph nodes shows that there is evidence of cancer cells in some of the lymph nodes, this means that the tumor has spread beyond the colon wall and entered the lymphatic system. This is a bad sign for the patient in most cases. While it is far from a death sentence, the lymphatic system is where the cancer cells spread in the bloodstream to other regions in the body. Evidence of cancer cells in the lymph nodes significantly reduces the patient's five year survival rate below 50%.
If there is evidence of cancer cells in other organs, such as the liver or brain, this is known as distant metastasis. This is an extremely bad sign for the patient. When the cancer cells have invaded other organs in the body, the fiv year survival rate is very low.
While the results of the pathological inspection of the lymph nodes are the most important test to determine the patient's five year survival rate, it is also important to ask the pathologist about the "surgical margin". When the tumor is surgically removed, the surgeon can have the tissue adjacent to the tumor checked microscopically by a pathologist for cancer cells. If the "surgical margin" is negative, this means that there were no cancer cells in the tissues surrounding the tumor. If the "surgical margin" is positive, there were cancer cells in the tissue adjacent to the tumor. The hope for all patients is that he/she has a negative margin. You should ask the surgeon: "Did I have a negative or positive surgical margin?"
Until you get the informaton about the pathology of the lymph nodes, you should not speculate about your prognosis. The bottom line about your prognosis for colon cancer will not be known until the biopsy of your lymph nodes has been completed and only then will your oncologist be able to assess your five year survival rate. Get answers from your surgeon and oncologist about the pathology results of your lymph nodes and get specific answers about your five year survival rate.
This article arms with you with the information you need and the questions that you need to ask your doctor.